This notebook was used by Edison during July-September 1916 for notes on experiments to improve the surface quality and the durability of disc records. There are also notes by Archie D. Hoffman and other experimenters. The entries pertain primarily to experiments 1238E through1261E. Included are tests involving different presses and varnish compounds, as well as variations in the amount of heat and pressure during baking. Flaws and successful results are both noted. A notation on experiment 1257 indicates that the resulting blank "appears to be the best blank and record we ever had & should be made standard." Also included are two lists of flaws observed in discarded record molds, numbered 41-199 and 1-48. At the end of the book are notes on the number of "girls" employed in the Disc Department, as well as notes about piece work rates, inspection standards, the number of records and molds produced, the number of discards, and the results of "drop tests." Some notes are in the form of instructions to Hoffman. Inserted into the book are several communications addressed to Edison from G. H. Baldwin, Joe Miller, and John F. Ott. The front and back covers are labeled "17." The pages are unnumbered. Approximately 100 pages have been used. Courtesy of Thomas Edison National Historical Park.